This invention relates to polymer compositions. In particular, this invention relates to soft, flexible polymer compositions with improved abrasion resistance. One aspect of this invention relates to polymer compositions containing linear or substantially linear .alpha.-olefin polymers and high molecular weight polydimethylsiloxane. Another aspect of this invention relates to polymer compositions containing linear or substantially linear .alpha.-olefin polymers in which the addition of polydimethylsiloxane does not substantially affect the coefficient of friction of the polymer composition nor the adhesion or heat seal strength of the composition. In yet another aspect, this invention relates to articles made from the above-mentioned polymer compositions.
Applications such as tarps, shoe soles, wire and cable insulation and jacketing where surface abrasion may occur require flexible polymers with good surface abrasion resistance. Low density (density &lt;0.9 g/cm.sup.3) ethylene/alpha olefin copolymers have good flexibility and toughness and thus are candidates for these applications; however, the low density polymers lack the surface abrasion resistance needed for these applications. Furthermore, although additives exist which may improve the processability and other properties of the polymer composition, these same additives can change the coefficient of friction (COF) and create undesirable effects in particular applications such as in shoe soles, where surface traction is important.
A polyolefin composition is needed which has improved abrasion resistance. Another desirable feature of such a polyolefin composition is that it possess a desirable coefficient of friction. Yet another desirable feature of such a polyolefin composition is that it be easily processed, thus requiring less energy to process. These and other advantages are taught by the polyolefin composition of the present invention.